Studies have shown that patients who miss HIV clinic appointments are more likely to have advanced disease, to develop opportunistic infections and to die. HIV/AIDS disproportionately affects those in the lower socioeconomic strata of the US and these persons are at high risk for poor health literacy. Patients with limited health literacy may not have the requisite skill to effectively understand and act upon the need to maintain regular HIV care. Although low health literacy has been linked to poorer health status, increased hospitalization rates and non-adherence to medications across a number of diseases including HIV, little is known of its effects on adherence to routine clinical appointments. Furthermore, cognitive impairment associated with HIV infection itself may be a risk factor for missed appointments. Despite treatment with HAART, substantial numbers have deficits in memory, information processing speed and other higher order cognitive functions requiring organization, planning and sequencing, the very cognitive skills needed for appointment making and keeping. No studies on the effects of literacy on healthcare utilization to date have accounted for cognitive impairment. Moreover, the literacy and cognitive challenges common in persons infected with HIV may also affect interactions with care providers and others in the social network. Both satisfaction with HIV care providers and social support are linked to better appointment-keeping behavior in HIV and may confer protection against the potential effects of poor literacy and cognition on missed appointments. This study therefore proposes to prospectively identity factors associated with later non-adherence to outpatient HIV clinic appointments in a sample of 175 HIV positive men and women followed prospectively for 7 months. Appointment adherence will be assessed through self-report and verified via medical records. The following are our aims: 1). To assess the ability of baseline literacy for health related information and neurocognitive ability to predict attendance at routine HIV clinic appointments;2). To assess the relative contribution of baseline literacy for health related information, neurocognitive ability, social support, and patient-provider communication to adherence to routine HIV clinic appointments;3).To assess potential moderating effects between health literacy and social support on missed HIV medical appointments. PUBLIC HEALTH RELEVANCE: Studies have shown that those who miss HIV clinic appointments are more likely to have advanced disease, to develop opportunistic infections and to die. Missed appointments may also be indirectly tied to HIV transmission since persons with higher levels of viremia are more likely to transmit the virus to others. Therefore, identifying characteristics of individuals at risk for poor adherence to HIV outpatient appointments is essential for developing interventions/programs that assist patients to adhere to their appointments, maximize the benefits of available treatment, and minimize the potential for future spread of the virus.